1294 Salix capreaCommon Names: goat willow,pussy willow,Kilmarnock willow,florist’s willow,sallow Family: Salicaceae (willow Family)
Goat willow is a small tree or large shrub that can get 15-25 ft (4.5-7.5 m) tall. It has broadly elliptic to oblong leaves, 2-4 in (5-10 cm) long and 1-3 in (2.5-7 cm) wide. The leaves, borne alternately along the stems, are dark green above, grayish and hairy beneath, and (usually) faintly toothed on the margins. Twigs are rather thick and yellowish brown. The species is dioecious with male and female flowers on separate plants. The male catkins are 1-2 in (2-5 cm) long, soft and wooly, and pinkish-gray, with conspicuous yellow anthers. They are quite showy. Female catkins (on separate trees) are smaller and greenish gray, and not nearly as showy as the male’s. The catkins are produced on leafless shoots before the leaves emerge in spring.
For many, goat willow is known primarily by the cultivars ‘Pendula’ (female) or ‘Kilmarnock’ (male). On their own, these selections are prostrate shrubs with crooked branches, that grow in trailing, ground cover-like mounds. However, they usually are grown as weeping standards, grafted to erect seedlings, and appearing as mop-like little trees with a dense crowns of pendulous yellow-brown shoots clad in drooping dark green leaves. The female clone is sometimes called ‘Weeping Sally’, and is the one most often found in American gardens.
Goat willow (Salix caprea) is often confused with pussy willow (S. discolor), a species native to eastern North America. Goat willow has leaves that are hairy and grayish beneath, whereas pussy willow has leaves that are bluish and hairless beneath. Goat willow has larger male catkins. Also, goat willow has yellowish brown twigs, and pussy willow has dark brown twigs.
Less common is the cultivar ‘Variegata’, which bears leaves with white markings but is not a weeping form.
Salix caprea grows wild in wetlands and moist, open areas throughout much of Europe and northeastern Asia. This ornamental, long popular in North America, has escaped cultivation and become established in parts of the northeastern US and Ontario.
Light: The willows are best grown in full sun. Moisture: Goat willow likes a moist but well drained soil. Once established, after a period of regular watering, they can tolerate drier soils better than the native American pussy willow. Hardiness: USDA Zones 4 - 8 . Propagation: Softwood cuttings root readily. Willows are dioecious, and only the female plants produce seeds, but male plants for pollination must be nearby. Willows are pollinated by bees. Seed should be surface sown as soon as ripe in late spring. Seeds often turn out to be sterile, and even fertile seeds lose viability quickly. They are very tiny and dispersed on the wind.
Goat willow is considered by many to be a better ornamental “pussy willow” than the native American species, Salix discolor. The catkins are larger and more showy than its American cousin, and the plant itself seems to be less susceptible to disease and more tolerant of dry soils. For ornamental purposes, select a male plant because these have the larger, showier flowers. Goat willow is fast growing and short-lived, but tolerant of urban air pollution and maritime exposure.
Use goat willow in moist locations, alongside a pond or in a drainage area. It is particularly useful in a rain garden. Goat willow, like most willows, tolerates heavy pruning and can be cut back regularly for use in a hedge or even cut to the ground every few years to maintain a small size. If not pruned regularly, the fast growing goat willow will become leggy and some branches will break off. The wood is soft and weak.
Kilmarnock willow (Salix caprea ‘Pendula’) is usually grafted onto an upright willow seedling (often the hybrid species, Salix X smithiana) to create a weeping standard, 5-6 ft; (1.5-2 m) tall, depending on the height of the graft union. These make noteworthy specimens in any landscape, but are especially valuable for smaller spaces. Left to its own and not grafted, Kilmarnock willow spreads out on the ground and could be used as a ground cover. ‘Weeping Sally’ is similar, but female.
The flowers, densely packed in the catkins, provide a valuable food source for bumblebees and other insects emerging from hibernation. The flexible stems are sometimes used for basket making.
The silky soft catkins suggest the alternate common name, pussy willow, but we use that name for the American species, Salix discolor.
There are some 300 species of willows worldwide, mostly in temperate and cold regions of the Northern Hemisphere.
Steve Christman 8/31/17; updated 2/24/18